1. Field of the Invention
The following disclosure relates to a developer container used for image forming, an image forming apparatus including the developer container and a method of forming a reinforcing member adhering to the developer container.
2. Description of the Background Art
The use of replaceable developer containers has widely been known to replenish developer consumed in a developing process of electrophotographic image forming. Such replaceable developer containers are replaced with a new or fully packed developer container whenever developer contained therein becomes short or is exhausted. Additionally, for environmental conservation, recycling of developer containers is highly desired.
In one technique, a developer container includes a flexible material so that the developer container can be compactly folded when developer in the developer container is fully consumed. This reduces a volume of the developer container, thereby reducing transportation cost in recycling. The developer container in the above-described technique is connected to a nozzle of an image forming apparatus with an opening of the developer container facing down to form a developer conveying mechanism. When the developer container and the nozzle are connected so as to not change a direction of a flow of developer, a total length of the developer conveying mechanism may be rather high. When the nozzle is designed to change the flow of developer so that, for example, developer can flow vertically in the developer container and horizontally in the nozzle, the developer conveying mechanism may still need a certain height. In this case, the image forming apparatus also needs a space that can accommodate the height of the developer container and the nozzle. Therefore, the above-described developer container creates size limitations for itself and the image forming apparatus.
In another technique, a developer container includes a guide member partly with fold parts so that the developer container can be compactly folded when developer in the developer container is exhausted. Further, the developer container having the guide member can promote the deformation of the developer container. Since the guide member is formed of material whose rigidity is higher than the developer container, when the developer container is deformed because of the reduction of the volume, the fold part of the guide member pushes the fold of the container. Also, the inner wall surface of the guide member uniformly pushes the plane part of the developer container. This reduces a volume of the developer container, thereby reducing transportation cost in recycling, as in the aforementioned technique.
However, the above-described techniques may still cause developer suction failure.
Referring to FIG. 1, a schematic structure of a background developer container 500 is described.
The background developer container 500 generally includes a bag-like developer case 501 packed with developer, a cap 502 connected to the bag-like developer case 501, and reinforcing members 503 attached to flat surfaces oppositely disposed to face to each other. The reinforcing members 503 provide higher rigidity to the flat surfaces than the other surfaces having folds F of the bag-like developer case 501. The cap 502 includes a nozzle-receiving hole 504 into which a cylindrical shutter member 505 is inserted.
Referring to FIG. 2A, a schematic structure of a developer conveying mechanism including the background developer container 500 is described.
The developer conveying mechanism includes the background developer container 500, a pump unit 600, and a developing unit 700.
In FIG. 2A, the background developer container 500 of FIG. 1 is connected to a nozzle 507 at the cap 502. Developer from developer container 500 is communicated to the developing unit 700 via a developer conveying tube 508. The developer conveying tube 508 is connected to the nozzle 507 at one end and to the pump unit 600 at the other end.
The pump unit 600 delivers developer stored in the developer container 500 to the developing unit 700 by creating suction through the developer conveying tube 508.
The developing unit 700 develops a toner image formed on an image bearing member provided in an image forming apparatus.
As previously described, developer contained in the developer container 500 is supplied to the developing unit 700 by suction created by the pump unit 600 according to consumption of developer. In a case in which the reinforcing members 503 are formed to have a flat shape or a concave shape with respect to the respective flat surfaces of the background developer container 500, as the developer is constantly consumed, the developer container 500 may be deformed as shown in FIG. 2A. FIG. 2B shows a deformed shape of the background developer container 500, viewed from A. That is, when most of the developer is already conveyed out from the developer container 500, the developer container 500 may have portions indicated by B and C. The flat surfaces with the respective reinforcing members 503 attached thereon are in close contact with each other or are hermetically closed at the portion B, while developer remains at the portion C. This could cause a developer suction failure, followed by a developer conveying failure. That is, if the pump unit 600 mostly sucks air, an amount of developer to be conveyed per unit of time may intermittently fall below a desired amount of developer to be conveyed, which may eventually stop a flow of developer to be discharged out from the developer container 500 and leave some developer unused.